I know this may be a Zebra/ripd problem rather than strictly ppp and
I've posted on the Zebra mailing but since it involves PPP, too, I
hoped someone here may have some relevant experience to share.

I'm using ppp 2.4.4b1 and ripd (from Zebra 0.94) in two embedded
systems using ARM
processors. I have one ARM7-based system and one ARM9-based system.
The ARM7-based system has worked for a year or more without a hitch
and
continues to work in a new build of my firmware. The same source
built
for ARM9 (a faster system with more memory) won't send RIP messages
when
the system initiates a PPP link. The messages I see in my ripd log
are:

I've Googled the messages above and found a couple of unanswered
questions, one which included a patch that's already in my source, and
nothing else that seemed to address my problem.

The best theory I have is that because my new, ARM9 system is faster
and
has more resources, that the thread which reacts to the PPP connection
being up is responding more quickly than it did on my ARM7 system but
if
I read the code right, there's a 1-second delay in starting that
thread
and it seems unlikely that the difference in timing on the two
processors would be an appreciable percentage of a second.